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Technical & Reference Section => Tech and Restoration => Topic started by: erniemadden on February 18, 2010, 10:02 PM

Title: Crank fitting
Post by: erniemadden on February 18, 2010, 10:02 PM

after copping the hump with my flights because I did not have the right allen keys, I turned from old to new skool and tried to bung some cranks on my rider, but I can't get this new skool crank to run true.
So I have a primo crank, 4 washers and a profile chainring.
1st thing are they compatible?
2nd how the F*** do they go together.
I have tried washers in between chainring and pedal arm no washers and washers on the otherside of the pedal arm.
So what am I missing?

(http://www.radbmx.co.uk/archive/albums/h165/erniemadden/SNC00009.jpg)


oh if anyone knows the size of the allen keys for the flights it may be helpful  ;)

Title: Re: Crank fitting
Post by: HEYWOOD BMX on February 18, 2010, 10:11 PM

 :) Not sure a Profile sprocket (usually have a 22mm centrehole without tophat washer) will fit onto a Primo axle,also 22mm...

Title: Re: Crank fitting
Post by: erniemadden on February 18, 2010, 10:21 PM

thanks for the info, but you will have to excuse my ignorance.
what is a top hat washer and if the chain will does not fit do you reccomend a Primo chain wheel?

Cheers....Steve

Title: Re: Crank fitting
Post by: HEYWOOD BMX on February 18, 2010, 10:27 PM

  This could take a while! Have a look at this,might be of some help? Think this shows a Profile type 48 spline crank & a Euro bottom bracket but the basic principles are the same.

http://www.parktool.com/repair/readhowto.asp?id=143
 

Title: Re: Crank fitting
Post by: erniemadden on February 18, 2010, 11:28 PM

thanks for the link that makes things clearer.   :daumenhoch:
Choosing a suitable chainring is a mindfield.
Any suggestions?

Title: Re: Crank fitting
Post by: HEYWOOD BMX on February 18, 2010, 11:59 PM

Loads to choose from.Have a look in the Rad shop-Stodgy will be able to answer any questions/provide tech know how.Don`t forget to get one that is compatible with your rear sprocket.


 http://www.radbmxshop.co.uk/shop/category_17/Sprockets.html'shop_param=cid%3D%26

Title: Re: Crank fitting
Post by: erniemadden on February 19, 2010, 12:05 AM

Thanks for your help  :daumenhoch: I am out Saturday and am going near the shop, so I will pop in.

Cheers...Steve

Title: Re: Crank fitting
Post by: gobshite on February 19, 2010, 01:48 AM

(http://www.radbmx.co.uk/archive/albums/g171/jarvicseven/51HzwnoZ8IL_SL500_AA280_.jpg)

(http://www.radbmx.co.uk/archive/albums/g171/jarvicseven/m_21-117p.jpg)

Title: Re: Crank fitting
Post by: erniemadden on February 19, 2010, 12:48 PM

Thanks for the pics mate, but I am not sure why they are there?
Are you saying that I need more bits for my crank?

Cheers...Steve

Title: Re: Crank fitting
Post by: erniemadden on February 22, 2010, 10:52 PM

after a bit of swotting up, i think I fully get it now and Mr. Heywood, looks like you were spot on with the incompatabillity between primo/profile.
So just for information before anyone else goes down the same road.

Stodgy helped me out by looking to see if there was a washer that fitted. No luck really  :(
After a bit of reading, found that the Chainwheel is a profile imperial and the hole is a bizzare 22.2 mm and that the top hats fit but only for a 19mm axle and not a 22mm  :tickedoff:

I intend to ride this bike, so I will need to get  it done as the chainwheel flaps like an old Thompson twins 12" that has been left in the sun.
So a trip to Radshop Saturday for a new chainwheel. Can't be bothered to fanny around, i am doing enough of that with the old skool, so I will just buy a new un...